- #1
david90
- 312
- 2
I have a scooter with a 5 inch diameter wheel and I want to make it go 25mph with a motor that has this specs.
====
Power 0.35 hp @12v 1.43 hp @24v
Torque 0.47 lbf*ft @12v 0.97 lbf*ft @24v
Efficiency 70% @12v 76% @24v
Speed 1260 RPM / Volt
Voltage 12 volts or 24 volts*
Weight 11 oz.
Output Shaft 5mm dia x .75" long
Diameter 1.7"
Length 2.8" (from face)
Face Mount 2 M4 holes 1.14" apart
===
I use this equation to figure out the RPM of the wheel for 25mph.
RPM*(((D*3.14)/12)*60)/5280)=MPH
Calcuated RPM for 25mph is = 1680 RPM
i'm planning to use 17 volts, thus the motor rpm would be 1260*17=21420 RPM
Now I'm finding the gear reduction. 21420/1680= 12.75
5"/12.75 thus .39" is the required gear size that is attached to the motor.
Is the .39" gear size the diameter, radius or circumference?
i'm not using a sprocket because it is friction drive.
Are there any potential problems with this setup? Is my calculation correct?
====
Power 0.35 hp @12v 1.43 hp @24v
Torque 0.47 lbf*ft @12v 0.97 lbf*ft @24v
Efficiency 70% @12v 76% @24v
Speed 1260 RPM / Volt
Voltage 12 volts or 24 volts*
Weight 11 oz.
Output Shaft 5mm dia x .75" long
Diameter 1.7"
Length 2.8" (from face)
Face Mount 2 M4 holes 1.14" apart
===
I use this equation to figure out the RPM of the wheel for 25mph.
RPM*(((D*3.14)/12)*60)/5280)=MPH
Calcuated RPM for 25mph is = 1680 RPM
i'm planning to use 17 volts, thus the motor rpm would be 1260*17=21420 RPM
Now I'm finding the gear reduction. 21420/1680= 12.75
5"/12.75 thus .39" is the required gear size that is attached to the motor.
Is the .39" gear size the diameter, radius or circumference?
i'm not using a sprocket because it is friction drive.
Are there any potential problems with this setup? Is my calculation correct?
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